High-pressure rotary joints: mechanical seal to prevent leakage of liquid pump is key

1. Access between the sealing surface; 2. Rotating surface and spindle access between the; 3. Fixed surface and gland access between the; 4. Gland and access between the packing box. The latter two leakage pathways general use of the static seal, between two parts because there is no relative movement. This part of the seal is usually called three seal, its sealing material for gaskets or and process flow liquid adaptation of the type O sealing ring. In older seal design, is located in the rotation of the second sealing face with a space, can be in the spindle before and after exercise, so easy to ring slip cause wear and premature failure. However, in a new seal design, the second sealing dormant, so it can avoid the spindle wear to appear on corrosion problems. In the normal operation of the pump, rotating face and still face for packing box of the fluid in between the pressure produced and to keep it in sealed condition, in the start and stop, packing box pressure produced by the spring pressure of maintaining (can be even by the spring pressure to replace).

Most of the mechanical seal design are a soft material to make rotation face, in the harder still face rotating friction. For many years, the most common is to use carbon materials as a combination of rotating face, in the ceramic still face operation. This kind of material is still widely used, but still face chooses stainless steel or more hard material production, such as tungsten carbide or silicon carbide. No matter what the material, in short in response to a layer of liquid between must keep thin film to Mercury Slip Rings lubricate role. However, in the packing box, the usual spring load and the way of the combination of the liquid pressure, can make between sealing plays very good sealing function. But the sealed pressure is too high, can affect formed between liquid film interface, resulting in increased and premature wear of the heat.

If sealing pressure is too low, the interface of the gap between increases, easy to cause the liquid leakage. Seal factory continues to revolving joint efforts to improve the surface straightness. They adopt special throw ground reflex. Then, using monochromatic light source the detection of grating slabs. From this point of view, the seal surface must be careful treatment, and strictly according to the installation instructions. Guarantee seal face gets proper protection and correction in place. This is very important